Four Hampshire and Isle of Wight police officers are being investigated for potential gross misconduct following the death of a 23-year-old man who became unwell after being arrested in Portsmouth.
The Independent Office for Police Conduct has launched an investigation into the actions and decision-making of the four constables who came into contact with Nigel Lawrence on 22 June.
The police watchdog said body-worn video showed Mr Lawrence, who was from Portsmouth, walking in the road among busy traffic on Fratton Road.
He then approached a police car containing two officers who were transporting another suspect to custody and opened one of its rear doors.
According to the IOPC, Mr Lawrence appeared distressed, was speaking incoherently and had what appeared to be white foam around his mouth.
Officers handcuffed and searched him before finding what the watchdog described as unlawfully controlled drugs and placing him under arrest.
Mr Lawrence was then put inside a police van to be taken to hospital because officers were concerned about his condition.
During the journey, the officers pulled over and began giving him emergency first aid, with paramedics later arriving to assist.
Mr Lawrence was taken to hospital but died the following evening.
A post-mortem examination was carried out on 1 July, although further tests are still being conducted and an inquest has not yet opened.
The IOPC investigation will examine the decision to search, arrest, handcuff and detain Mr Lawrence, as well as the care he received.
All four officers have been advised that they are under investigation for potential breaches of police professional standards which could amount to gross misconduct.
However, the watchdog stressed that the serving of investigation notices does not mean misconduct has been proven or that disciplinary proceedings will necessarily take place.
IOPC Director of Engagement Derrick Campbell said the independent investigation was needed to establish the full circumstances because Mr Lawrence had been in police custody when he became unwell.
The watchdog said it had met Mr Lawrence’s family to explain the investigation and would keep them updated as it progressed.
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